public static Tuple <List <Expression>, List <Expression> > ExtractKeyNodes(Expression expression, ParameterExpression thisParameter, ParameterExpression otherParameter)
{
var walker = new EntityMatchWalker(thisParameter, otherParameter);
walker.Visit(expression);
return(Tuple.Create(walker._thisKey, walker._otherKey));
}
private static void SetFieldByKeys <TParent, TChild>(
PropertyAccessor <TParent, TChild> schema,
IList <TParent> parentEntities,
IList <TChild> childEntities)
where TParent : class
where TChild : class
{
var predicate = schema.AssociationDescriptor.GetPredicate(typeof(TParent), typeof(TChild))
as Expression <Func <TParent, TChild, bool> >;
if (predicate == null)
{
predicate = (p, o) => true;
}
var keyTuple = EntityMatchWalker.ExtractKeyNodes(predicate,
predicate.Parameters[0],
predicate.Parameters[1]);
var thisKeyExpressions = keyTuple.Item1;
var otherKeyExpressions = keyTuple.Item2;
var otherKeys = KeyExpressionsToKeyHolder(schema.AssociationDescriptor.OtherKey, otherKeyExpressions);
var thisKeys = KeyExpressionsToKeyHolder(schema.AssociationDescriptor.ThisKey, thisKeyExpressions);
if (otherKeys.Any() && thisKeys.Any())
{
var hasher = _fkHashFuncs.GetOrAdd(new FKHashFuncKey
{
OtherType = typeof(TChild),
OtherKeys = otherKeys.ToList(),
ThisType = typeof(TParent),
ThisKeys = thisKeys.ToList()
}, k => new FKHashCodeFunc <TParent, TChild>(CreateGetHashCodeFunc <TParent>(thisKeys),
CreateGetHashCodeFunc <TChild>(otherKeys),
predicate.Compile()));
var typeHasher = hasher as FKHashCodeFunc <TParent, TChild>;
var childLookup = childEntities.ToLookup(typeHasher.OtherHashCodeFunc);
MatchEntityLookup(schema, parentEntities, typeHasher.AssociationPredicate, childLookup, typeHasher.ThisHashCodeFunc);
}
else
{
MatchEntityList(schema, parentEntities, childEntities, predicate.Compile());
}
}